As stated in Applicants' U.S. Pat. No. 4,141,175, current world food strategy relies heavily upon the use of improved technology. The societal need is now well established for a new, relatively low cost, minimally energy-consuming process for the production of fixed nitrogen that can be put into service with much lower capital outlay than existing technology offers and has the advantage of eliminating transportation costs.
Increased cost of nitrogen fertilizer is only one of the many results of an increasing world demand for food and a decreasing supply of natural gas and liquid hydrocarbons which provide the primary source of hydrogen used in their production. Long range solutions to the world food problem will require that more and more countries develop the capability to feed themselves rather than be dependant on ever increasing production from areas of the world which are currently experiencing high yields. This will be necessary not only for economic reasons (an underdeveloped country's ability to purchase in a competitive world market), but also to minimize the global effects of unfavorable weather or other natural disasters occuring in one of the high yield areas of the world.
The world food problem is increasing the demands for nitrogen fertilizer at a time when supplies of natural gas and other fuels used in their production are decreasing and becoming more expensive. One method to compensate for present and future shortages of nitrogen fertilizers is to produce nitrate fertilizer from air and water using electric arc discharge in air processes. However, to make electric arc discharge processes economically competitive, the need exists for a compact nitrate fertilizer production unit specifically designed for installation and use at the point of fertilizer application. Nitrate fertilizer generating systems installed on site can virtually eliminate storage, transportation and capital amortization costs which account for more than two thirds of the price of present day nitrogen fertilizers.
Prior to the development of the Haber-Bosch process for the production of ammonia fertilizer, a wide variety of methods were explored for the oxidation of nitrogen to nitrate fertilizers. Some of the more pratical methods that evolved into commercial nitrate fertilizer production systems were based on the principle of combining the nitrogen and oxygen of air by means of various electrical arc discharge processes. However, to be economically competitive with natural fertilizer at that time, most of the arc process systems developed were located near large hydroelectric generating plants to minimize electrical power costs. With few exceptions, rural electrification did not exist. Consequently, line powered nitrate fertilizer generators were neither practical nor, perhaps, even considered.
With the advent of the Haber-Bosch process, using relatively inexpensive hydrogen obtained from natural gas and liquid hydrocarbon sources, the electric arc processes ceased to be competitive and were generally abandoned. It was found to be more efficient to use the same electrical energy to hydrolize water to produce hydrogen as the feed stock for the Haber-Bosch process.
Today, even with the shortage and increased cost of natural gas, calculations indicate that electric arc processes for the production of nitrate fertilizer probably could not be competitive if storage, transportation, distribution, and capital amortization costs were excluded. The largest proportion (often exceeding 75%) of the delivered price of anhydrous ammonia comes from costs other than actual production. Expensive storage and distribution costs generally arise since the ammonia production plants necessarily must be located close to large quantities of natural gas. Fertilizer usage is highly seasonal, but large Haber process plants must be operated on a continual basis such as 360 days per year to be cost efficient. With shortages of fossil energy becoming ever more acute, transportation costs will naturally increase and also create a double (one to produce-one to transport) expense from an energy economics point of view.